// Principal (parent)public class Blog{ public int Id { get; set; } public ICollection<Post> Posts { get; } = new List<Post>(); // Collection navigation containing dependents}// Dependent (child)public class Post{ public int Id { get; set; } public int BlogId { get; set; } // Required foreign key property public Blog Blog { get; set; } = null!; // Required reference navigation to principal}
protected override void OnModelCreating(ModelBuilder modelBuilder){ modelBuilder.Entity<Blog>() .HasMany(e => e.Posts) .WithOne(e => e.Blog) .HasForeignKey(e => e.BlogId) .IsRequired();}